U.S. Pat. No. 4,255,003 discloses a contact device for providing electrical connection between conductor runs of a hybrid integrated circuit and conductor runs of a printed circuit board. The contact device is a frame-like structure comprising a body of elastomeric material having strips of metal bonded to a surface region of the body, and a clamping member. The metal strips may comprise a base layer of copper-beryllium, a layer of nickel and a layer of gold. In use of a practical implementation of the contact device, the substrate is placed on top of the circuit board, and the clamping member is used to urge the body of elastomeric material into contact with the upper surface of the circuit board and the upper surface of the ceramic substrate. The metal strips provide electrical connection between the conductor runs of the hybrid integrated circuit and the conductor runs of the circuit board. The metal strips are of substantially the same width (0.64 mm) and at substantially the same spacing (0.64 mm) as the terminal areas of the conductor runs. A disadvantage of the device described in U.S. Pat. No. 4,255,003 is that dust or dirt on the terminal areas of the conductor runs or on the metals strips degrade the electrical connection between the conductor runs. This problem could be alleviated if the metal strips were considerably narrower than, and at considerably smaller spacing from, the terminal areas of the conductor runs, so that contact between terminal areas of corresponding conductor runs would be provided by two or more metal strips, in that even if the contact through one strip were degraded it is unlikely that the contact through the other strip(s) also would be degraded. However, the metal strips would then have to be very narrow, e.g. about 0.13 mm, and would therefore be very frail. Such narrow metal strips, if bonded directly to the body of elastomeric material as in the case of U.S. Pat. No. 4,255,003, would have to be etched after bonding in order to avoid damage during handling. However, if the metal strips are of the layered structure described above, the copper-beryllium alloy is liable to be undercut by as much as 0.08 mm if the strips are patterned by conventional selective etching techniques, and this places a lower limit on the width of metal strips that can be formed on a body of silicone rubber in this manner.